Murphy went into full cardiac arrest last night and could not be revived, according to TMZ. The Los Angeles Fire Department tells the site they received a call from a home belonging to Murphy's husband, Simon Monjack. The actress was pronounced dead on arrival at Cedars-Sinai Medical Center.
She was 32.
The Atlanta-born actress began acting in local theater productions when she was just 9, and by age 13 she was starring in television commercials, according to TheWrap.com.
After having starred in films including "8 Mile," "Don't Say A Word" and "Clueless," Murphy had found herself busy with work again recently, with starring roles in at least four upcoming films. She is rumored to have been fired from one recent role for being difficult on the set, but she denied the report in a recent story in OK Magazine.
"Due to creative differences, Ms. Murphy and the production company mutually parted ways," her rep said.
Murphy had also voiced the part of LuAnne Platter on the animated comedy, "King of the Hill," since 1997.
"2day the world lost a little piece of sunshine," Ashton Kutcher, who dated Murphy in 2002 - 2003, posted on Twitter on Saturday. "My deepest condolences go out 2 Brittany's family, her husband, & her amazing mother Sharon. see you on the other side kid."